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Nb、Ti微合金化新型440MPa级船用钢板韧性研究 总被引:1,自引:1,他引:0
研究了某钢厂热连轧TMCP工艺14mm厚440MPa级钢板的强韧性,对微观组织进行了观察分析.试验结果表明,新型热连轧440MPa钢板具有良好的低温韧性,-40℃冲击功超过310J,韧脆转变温度低于-100℃.新型440MPa钢板良好的性能来源于低碳、Nb-Ti微合金化成分设计及TMCP工艺下获得细化的针状铁素体组织. 相似文献
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研究了DP590低成本热轧双相钢采用合适的焊丝、焊剂及合理的焊接工艺后,钢板焊接接头的拉伸性能、冲击韧性及硬度的变化情况。证明了实验钢具有优良的抗软化能力和冷弯成型性能且淬硬倾向不明显。实验表明,开发的DP590低成本热轧双相钢焊接性能优良,适于焊接制造汽车车轮、横梁、纵梁等构件。 相似文献
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为了评价Q345qNHY新型跨海桥梁用钢的焊接性能、为工程应用提供依据,通过拉伸、冲击、弯曲和硬度等试验方法对其对接接头的力学性能进行了研究。结果表明:采用JW-55W焊丝对Q345qNHY耐候桥梁钢进行焊接时,获得的焊接接头具有较好的拉伸性能、弯曲性能和优异的低温冲击韧性。试验采用的焊接材料和工艺参数可用于19—33mm厚度Q345qNHY钢板的平位对接。 相似文献
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为了研究在不同爆炸焊接工艺条件下获得的复合板的轧制效果,本文对大波、小波、微波状3种界面的1Cr18Ni9Ti/20G复合板进行轧制实验研究.实验表明:只有用下限获得的微小波状界面的爆炸焊接复合板,才能实现成功轧制,而大波状复合板界面存在一定的缝隙、空洞等微观缺陷,在轧制时由于分层会使轧制失效.爆炸焊接 轧制工艺获得的复合板结合界面的组织、强度和性能的测试结果表明:轧制复合板结合界面的剪切和分离强度虽比爆炸态略低,但延伸率、冲击韧性都大大增强,轧制复合板的耐蚀性能也未降低. 相似文献
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轧制态高强度低合金(HSLA)钢板同热处理的HSLA钢板相比,具有许多优点。本文对于为研制通用于对强度要求颇高的海军造船用途的两种轧制态HSLA所进行的实验室研究和生产性研究进行了探讨。研究表明,一种用微量铌、钒进行合金化的低碳钢具有强度、韧性和可焊性三者有利配合的综合性能。研究结果表明,可以生产出满足现有HSLA-80强度和冲击性能要求的轧制态HSLA-80钢板,其最大厚度为19mm左右,而可以生产的HSLA-60钢板的最大厚度约为51mm,这种轧制态HSLA钢板通常可以在不预热的条件下,用NY-80焊接材料予以焊接。 相似文献
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采用KONTC00L工艺(一种将控制轧制和加速冷却结合起来的新方法)研制出屈服强度36公斤力/毫米~2的低碳当量船体结构钢板。本工艺的形变热处理作用可以减少钢板的碳当量,并改善基体金属的韧性。KONTCOOL钢板可在不预热的情况下焊接,即使在500千焦耳/厘米这样的大线能量下焊接,焊接接头热影响区仍有令人满意的韧性。 相似文献
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利用正交试验法,研究了焊接工艺参数对X65管线钢管闪光对焊焊接接头力学性能的影响。正交试验中选择激发闪光阶段烧化量、稳定闪光阶段烧化量、稳定闪光阶段焊接电流、加速闪光阶段闪光速度作为试验因素,焊接接头抗拉强度、塑性和低温冲击韧性作为焊接工艺的评价指标,得到了最优的焊接工艺参数。接头的金相分析表明,焊接的高热输入使接头焊缝区和部分热影响区的晶粒粗化,形成魏氏组织,降低了接头的冲击韧性。刻槽锤断试验表明,灰斑缺陷内部和边缘的密集裂纹导致接头脆性解理断裂。加速闪光阶段优化的闪光速度有利于减少焊缝区内的缺陷并提高接头的力学性能。 相似文献
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英国潜艇用钢及其焊接材料 总被引:1,自引:0,他引:1
综述了英国潜艇用钢及其焊接材料和工艺最新发展情况,给出了钢板产品的成分性能数据,重点介绍了Q1N钢用焊接工艺的应用情况。在钢板和焊接接头性能验收方面,英国海军采用了与美国海军一些相对不同的考核试验方法,本文对这些试验方法作了简单的介绍。 相似文献
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《International journal for numerical methods in engineering》2018,113(9):1488-1506
In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method. 相似文献
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Steffen Müller-Probandt 《材料科学与工程:中英文B版...》2018,(4):161-177
We associate a variety of innovations with the term "Industry 4.0". The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di... 相似文献
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A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils. 相似文献
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Janet Lang 《Materials and Manufacturing Processes》2017,32(7-8):857-866
ABSTRACTThe production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them. 相似文献
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Standards are the basis for production enterprises to organize production ex-factory inspection trade 《中国标准化(英文版)》2008,25(1):24-25
Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.…… 相似文献
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A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa. 相似文献
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S. K. Malhotra Paramanand Singh A. Thirunavukkarasu 《Materials and Manufacturing Processes》2006,21(7):652-657
Al2O3-ZrO2 nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness. 相似文献
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The end of over unit products of more than Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits beer wine yellow wine fruit syrup wine others cover over % of the national top-branded liquor products.…… 《中国标准化(英文版)》2008,25(1):30
The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.…… 相似文献
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Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster. 相似文献